Seaweeds are considered as one of the most productive biomass resources on the earth. Among the number of other advantages, they don't compete for agricultural land for growth and expansion, they are naturally fertilized by ocean nutrients and hence there is no burden of fertilizer at all for their growth, their growth rate is very high in comparison to terrestrial plants, they can be cultivated and harvested multiple times in a year. Despite the huge potential, estimated about only 1% of macro algae resources are utilized till now and there is a tremendous opportunity to use the seaweeds as resource for the production of fine high value chemicals. Few species of brown seaweeds are being commercially exploited for the production of alginic acid and they are of interest in Europe due to their very high growth rate (131 t ha−1·Y−).
Reference may be made to the patent entitled “Method for preparing carbon material with graphene-like structure from biomass” [CN 103449399 A dated Dec. 28, 2013], which discloses a method of preparation of high-quality carbon material with graphene-like structure from biomass using microwave carbonization without any pretreatment of the starting material.
Reference may be made to the patent entitled “Method for preparing graphene with biomass-derived carbonaceous mesophase” [CN 102807210 B dated Jun. 25, 2014], which discloses a method of preparation of graphene from biomass comprising of impregnation of powdered monocrystalline silicon, polysilicon, mica or quartz in biomass-derived carbonaceous mesophase-ethanol solution followed by drying to obtain the base substance with surface attached by a layer of biomass-derived carbonaceous mesophase thin film.
Reference may be made to the patent entitled “One kind of graphene and graphene preparation” [CN 104386684 A dated Dec. 16, 2014], wherein various biomass used were pre-treated with sodium periodate in aqueous solution at 50° C. for 2 h followed by dissolution in sodium hydroxide solution and eventually pyrolysed in presence of various metal catalysts to get the graphene.
Reference may be made to the patent entitled “A method for preparing activated carbon/graphene composite” [CN 104118874 A dated Oct. 29, 2014], which discloses a method of preparation of a composite comprising of activated carbon and graphene obtained by uniformly mixing biomass, carbonitride and a transition metal compound followed by heating the mixture.
Reference may be made to the patent entitled “Preparation method of activated porous graphene with good conductivity and dispersibility from porous cellulose by bleaching, activation and carbonization” [CN 104118873 A dated Oct. 29, 2014], which discloses a method of preparation of activated porous graphene by hydrolysis of biomass resource (cornstalk, corncob, etc.) in acid (sulfuric acid, nitric acid, etc.) followed by activation and carbonization of porous cellulose thus obtained.
Reference may be made to the patent entitled “Method for preparing graphene three-dimensional hierarchical porous carbon material” [CN 104045077 A dated Sep. 17, 2014], which discloses a method of preparation of graphene three-dimensional hierarchical porous carbon material having wrinkle lamellar structure and microporous and macroporous multi-level pore structure using coconut shell, palm shells and apricot shells and other biomass as raw materials such as resource-rich bio-waste.
Reference may be made to the paper entitled “Shaped mesoporous materials from fresh macroalgae” [J Mat Chem A. 2013,1, 5203-5207] where a method for the preparation of low-density and highly mesoporous structures from seaweeds such as Laminaria digitata, Laminaria hyperborean, Saccharina latissima, Ascophyllym nodosum and Fucus vesiculosus by solvent exchange followed by drying was described.
Reference may be made to the paper entitled “Biosourced nitrogen doped microcellular monoliths” [Chem Sus Chem. 2014, 7, 397-401] where the microsized carbon monoliths were obtained by the treatment of phloroglucinol or 5-hydroxymethyl-2-furfuraldehyde or N-acetyl glucosamine with FeCl3.6H2O.
Reference may be made to the paper entitled “Water dispersible magnetite reduced graphene oxide composites for arsenic removal” [ACS Nano. 2010,7, 3979-3986] where Fe3O4 functionalized reduced graphene oxide was prepared by the reduction of graphene oxide using NH3 solution and hydrazine hydrate at elevated temperature and under acute alkaline conditions.
Reference may be made to the paper entitled “Seaweed derived heteroatom doped highly porous carbon as an electro catalyst for the oxygen reduction reaction” [Chem Sus Chem. 2014, 7, 1755-1763] where N and S doped porous carbon structure was obtained by the pyrolysis of Undaria pinnatifida without using any template.
Reference may be made to the paper entitled “Renewable nitrogen doped hydrothermal carbons derived from microalgae” [Chem Sus Chem. 2012, 5, 1834-1840] where N doped hydrothermal carbon was obtained by the hydrothermal carbonization of Spirulina platensis and mixture of the micro algae and glucose.
Reference may be made to the paper entitled “P-doped graphene obtained by the pyrolysis of modified alginate as a photocatalyst for hydrogen generation from water/methanol mixture” [Angew Chem Int Edn. 2013, 52, 11813-11816] where H2PO4− was added in colloidal solution of sodium alginate followed by pyrolysis and ultrasonication of the phosphorylated alginate mass.
Reference may be made to the paper entitled “Iron catalyzed graphitization of biomass” [Green Chemistry 2015, 17, 551-556] where soft wood was converted to graphitic carbon by graphitization by reacting with Fe(NO3)3 under inert atmosphere.
Reference may be made to the paper entitled “Graphene wrapped Fe3O4 anode material with improved reversible capacity and cyclic stability for Li-ion batteries” [Chemistry Materials 2010, 22, 5306-5313] where iron hydroxide was reduced in situ between the graphene nano sheets to yield graphene material wrapped with Fe3O4 suitable for energy storage applications.
Reference may be made to the paper entitled “P-n heterojunction of doped graphene films obtained by pyrolysis of biomass precursors” [Small 2014, doi 10.1002/smll.201402278] where nitrogen doped graphene having characteristics of n-type semiconductors was obtained by the pyrolysis of nanometric chitosan films. Similarly boron doped graphene having characteristics of p-type semiconductors were obtained by the pyrolysis borate ester of sodium alginate.
Reference may be made to the paper entitled “From biomass wastes to large area, high quality, N-doped graphene: catalyst free carbonization of chitosan coating on arbitrary substrates” [Chemical Communications 2012, 48, 9254-9256] where chitosan films were pyrolysed under argon atmosphere at elevated temperature to yield high quality single layer N-doped graphene film.
Reference may be made to the paper entitled “From coconut shell to porous graphene like nano sheets for high power super capacitors” [Journal of Material Chemistry A 2013, 1, 6462-6470] where porous graphene like nano sheets with large surface area was synthesized by simultaneous activation-graphitization of coconut waste shells using FeCl3 as catalyst and ZnCl2 as activating agent.
Reference may be made to an article entitled “Production of partially reduced graphene oxide nanosheets using a seaweed sap” [RSC Adv., 2014, 4, 64583-64588], wherein reduced graphene oxide nanosheets were obtained by the reduction of graphene oxide in the seaweed sap obtained by the mechanical crushing of Kappaphycus alvarezii seaweed.